RECTOVESICAL FISTULA - Report of an unusual case

CASE REPORT :

The following is a case of Imperforate anus for which he was operated. The patient came at 20 yrs of age with complains of decreased micturition and defecation.He was referred for IVP and RGU.
Upon IVP evaluation mild hydronephrosis was noted on both sides probably due to decreased micturition.
Also a radioopaque density was noted in the bladder area...Upon detailed history, the patient gave history of ingesting a coin in childhood which was seen in the bladder region. A small outpouching was also noted in the lower part of the bladder.

IVP Images : 

 

RGU : 

Upon RGU evaluation, the coin was confirmed to be in the rectum. It must've been impacted with fibrosis around it as the coin was ingested in childhood. Also the posterior urethra showed stricture formation with visualization of a rectovesical fistula.

Finally, the patient was referred to surgery department for closure of the fistula and treatment of the posterior urethral stricture.

DISCUSSION : 

Introduction

Normally, the urinary system is completely separated from the alimentary canal. Connections may result from (1) incomplete separation of the two systems during embryonic development (eg, failure of the urorectal septum to divide the common cloaca), (2) infection, (3) inflammatory conditions, (4) cancer, (5) trauma or foreign body, or (6) iatrogenic causes (presenting either postoperatively or as a treatment complication). In the general practice of medicine, bowel disease that occurs adjacent to the bladder and erupts into it is the most common cause of misconnection of the two systems. Fistulae from the bowel to the ureter and the renal pelvis are also possible but uncommon in the absence of trauma, chronic infection, or surgical interventions. This article focuses on the more common causes, presentations, and treatments of enterovesical fistulae.

Presentation

The presenting symptoms and signs of enterovesical fistulae occur primarily in the urinary tract. Symptoms include suprapubic pain, irritative voiding symptoms, and symptoms associated with chronic urinary tract infection (UTI). The hallmark of enterovesical fistulae may be described as Gouverneur syndrome, namely, suprapubic pain, frequency, dysuria, and tenesmus. Other signs include abnormal urinalysis findings, malodorous urine, pneumaturia, debris in the urine, hematuria, and UTIs

Imaging Studies

CT scanning
CT scanning of the abdomen and pelvis is the most sensitive imaging test for detecting a colovesical fistula, and CT scanning should be included as part of the initial evaluation of suspected colovesical fistulae. CT scanning can demonstrate small amounts of air or contrast material in the bladder, localized thickening of the bladder wall, or an extraluminal gas-containing mass adjacent to the bladder. Three-dimensional reconstruction is useful when traditional axial and coronal images fail to demonstrate the anatomy in sufficient detail.The images below show a series of CT scans.

Barium enema
Barium enema (BE) imaging is unreliable in revealing a fistula but is useful in differentiating diverticular disease from cancer. BE imaging can demonstrate the nature and extent of colonic disease. In a 1988 series, Woods et al used BE imaging to demonstrate fistulae in 42% of cases.

Ultrasonography
Ultrasonography of colovesical fistulae has been described. In some instances, the fistula is easily identified, with no additional maneuvers needed.Ultrasonographic examination of suspected fistulous sites has been enhanced with the technique of manual compression of the lower abdomen, which reveals an echogenic "beak sign" connecting the peristaltic bowel lumen and the urinary bladder. As with cystography, ultrasonography is rarely used for primary imaging of fistulae.

Cystography
Cystography may demonstrate contrast outside the bladder but is less likely to demonstrate a fistula.
Radiographic signs have been described. The herald sign is a crescentic defect on the upper margin of the bladder that is visualized best in an oblique view. The herald sign represents a perivesical abscess. A "beehive on the bladder" sign is associated with the vesical end of the fistulous tract.

Treatment

Medical Therapy

Nonsurgical treatment of colovesical fistulae may be a viable option in patients who cannot tolerate general anesthesia or in selected patients who can be maintained on prolonged antibacterial therapy for symptomatic relief.

Surgical Therapy

Open surgery
Colovesical fistulae can almost always be treated with resection of the involved segment of colon and primary reanastomosis. Fistulae due to inflammation are generally managed with resection of the primarily affected diseased segment of intestine, with repair of the bladder only when large visible defects are present. The bladder usually heals uneventfully with temporary urethral catheter drainage. Suprapubic tube diversion is an option but is not necessary
Endoscopic treatment
A review of the literature reveals one reported case of a colovesical fistula treated with transurethral resection with no evidence of recurrence in more than 2 years of follow-up
Laparoscopic treatment
Several reports suggest that laparoscopic resection and reanastomosis of the offending bowel segment is possible as a minimally invasive treatment